Modern industry piping uses rotary actuated valves such as ball or butterfly valves to control the flow of a process medium to and from equipment such as tanks and pumps. These valves use up to ninety degrees of rotation to span the full range of control. These valves may be manually operated with a handle actuated by a human process operator or actuated by other means such as compressed air, electric motors, hydraulic pressure, compressed springs and or combinations of these forces from remote locations. This combination of valve and powered actuator is called an automatic valve. Manually operated valves with a handle attached can usually be locked in any number of positions to suit plant conditions and meet regulatory requirements for personal safety during maintenance. Rotary actuated valves with automatic operators have had the manual lever replaced with a solid coupling to an operator and is controlled remotely. This automatic operator presents problems with providing a lock out of the valve as may be required to perform maintenance activities down stream of the valve. OHSA requires a physical device that prevents the unauthorized movement of the valve that might release hazardous energy when work is performed downstream.
One approach to this problem includes the addition of manual block valves downstream, in line with the automatic valves to provide a means to lock out hazards. The power to the automatic valve actuator may be locked out in some cases. The systems process medium can be flushed and drained. The actuator may be removed and the valve then fitted and locked with a handle and locking mechanism.
The additional manual block valves requires foresight in the design stage and adds expense. To remove the motive power to an actuator has very limited use, for example it may provide a undesired position on loss of power. It can take considerable time and expense to flush and drain a large system. Removing the actuator presents its own set of hazards.
It is therefore an object of the invention to allow greater flexibility in design of piping systems where maintenance activities will take place.
It is another object of the invention to allow existing installed automatic rotary actuated valves to be retrofitted with this device.
It is another object of the invention to allow existing installed valves being fitted with automatic actuators to incorporate this device.
It is another object of the invention to allow new automatic valves, being readied for installation, to have this device incorporated.
It is another object of the invention to allow any valve fitted with this device to be operated manually.
It is another object of the invention to allow any valve fitted with this device to be manually set to any position regardless of the automatic process input.
It is another object of the invention to allow any valve fitted with this device to be locked in any position required for OSHA compliance.
It is another object of the invention to have any valve fitted with this device to operate automatically when the handle is not inserted and in use.
It is another object of the invention to have any valve fitted with this device to provide a visual indication of automatic or manual operation to be indicated by the insertion of the lever.
It is another object of the invention to have any valve fitted with this device to provide a visual indication of the position of the valve when the valve is in the manual mode.